A semiconductor device including a memory cell region in which a memory cell such as a non-volatile memory is formed on a semiconductor substrate is widely used. For example, there is a case in which a memory cell having a split gate cell using a MONOS (metal-oxide-nitride-oxide-semiconductor) film is formed as the non-volatile memory. In this case, the memory cell is formed by two MISFETs (metal insulator semiconductor field effect transistor) composed of a control transistor including a control gate electrode and a memory transistor including a memory gate electrode.
This memory gate electrode is formed by leaving a conductive film on a side surface of the control gate electrode via an insulating film like a sidewall spacer. Also, between the memory gate electrode and the control gate electrode, and between the memory gate electrode and a semiconductor substrate, an insulating film having a charge storage unit inside is formed.
In Japanese Patent Application Laid-Open Publication No. 2006-332143 (Patent Document 1), disclosed is a technique of a semiconductor device including a non-volatile memory element formed on a semiconductor substrate in which the non-volatile memory element includes a control gate electrode and a memory gate electrode provided adjacent to the control gate electrode.
In Japanese Patent Application Laid-Open Publication No. 2006-41354 (Patent Document 2), disclosed is a technique of a semiconductor device in which a protruding active region is formed on a front surface of a semiconductor substrate, and in which a select gate or a memory gate is arranged to straddle the projected active region.